Thread: tach signal
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Old 10-08-2003, 10:10 PM
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sixto sixto is offline
smoke gets in your eyes
Join Date: Jun 2000
Location: SF Bay Area
Posts: 18,745
If there are wires sticking out the back of the AC compressor, the compressor has a rpm counter. The Klima relay compares the compressor to engine rpm to decide if the compressor is working properly. If the compressor is dragging or seized, the Klima relay cuts power to the compressor clutch to save the serpentine belt so as not to strand you. I don't know if nonUS cars have this feature.

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